JP2003234581A - Radio communications equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide radio communications equipment, showing high bright feeling without producing radio disturbances. <P>SOLUTION: Radio communications equipment includes a member obtained by molding a resin component including glass flakes or silica flakes, as they are, or including a bright pigment obtained, by coating the flakes with metal or metallic oxide, or a member having a coating film including the glass flakes or silica flakes or the bright pigment. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless communication device exhibiting a glittering and high brilliance.

[0002]

2. Description of the Related Art As a wireless communication device, for example, a transceiver, a cordless telephone or a personal digital assistant (PDA).
Have been commercially available. Currently, wireless local area networks (LAN) such as Bluetooth
Equipment using is sold. In addition, a "home gateway," which is a contact point that connects digital home appliances to the Internet, is currently under consideration, and it is expected that many electrical products, including home appliances, will be digitalized and wireless communication will be possible between them in the future. To be done.

Since these wireless communication devices transmit and receive radio waves to transmit information, their constituent members, especially the casing, which is the largest constituent member, are required not to cause radio wave interference. Therefore, metal housings have traditionally been shunned,
The thing made of resin is generally used. In particular, since the housings have become smaller and the number of wireless communication devices with a built-in antenna has increased due to the portable use of the wireless communication devices, the degree of influence of the radio wave interference due to the housings has become larger than before.

Further, if the wireless communication device becomes portable, its designability becomes an important judgment factor in selecting a purchased device. In order to improve the design of the wireless communication device, the member may contain a luster pigment. This luster pigment is pre-blended in the resin composition of each member before molding, or blended in the paint applied after molding of each member so that it is present on the outer surface of each member. To be done. The luster pigment reflects light, so that each member has a glittering appearance. By the way, a wireless communication device that gives off a bright feeling seems to give a mechanical impression to human psychology, and it seems that the wireless communication device is selling better than a device that does not give a bright feeling. In this respect, the glittering feeling is important in the appearance of the wireless communication device, and it can be said that it has an influence that influences the sales of the product.

As the luster pigment, flaky aluminum powder, mica particle particles coated with a metal oxide such as titanium dioxide or iron oxide, graphite particle particles or iron oxide particles containing α-iron oxide crystal particles as a main component. Are well known.

[0006]

However, metal powder such as aluminum powder is not suitable for use in radio communication equipment because it has conductivity and magnetism and shields radio waves. In addition, mica pieces (pearl mica) coated with titanium dioxide, etc., do not have a radio wave shielding property, but the surface smoothness is low, so that the brilliance is likely to be insufficient. Particles were crushed during the kneading of
There is a problem that the glittering feeling is further reduced. Furthermore, the graphite particles coated with a metal oxide have a problem that the black range of the graphite is reflected in the appearance thereof, so that the range in which they can be used for design is limited. Further, since the α-iron oxide crystal particles also exhibit a brown color or a black color, there is a problem that the range in which the α-iron oxide crystal particles can be used for design is limited like the graphite particles.

The present invention has been made in view of the above problems. The purpose is to coat glass flakes with high surface smoothness as they are, or to coat the surface with a metal or a metal oxide, and mix them in a resin composition or a paint, and to use this resin composition in a housing or the like. By molding into a member that is easily noticeable in appearance or by coating a film on the surface of that member, without causing radio interference,
It is to provide a wireless communication device that exhibits a high brilliance.

[0008]

In order to achieve the above object, the wireless communication device of the invention according to claim 1 is a member formed by molding a resin composition containing glass flakes or silica flakes, or glass flakes. Alternatively, it includes a member provided with a coating film containing silica flakes.

According to a second aspect of the present invention, there is provided a wireless communication device,
It includes a member formed by molding a resin composition containing a bright pigment in which glass flakes or silica flakes are coated with a metal or a metal oxide, or a member provided with a coating film containing the bright pigment.

According to a third aspect of the present invention, there is provided a wireless communication device,
In the invention of claim 2, the bright pigment is glass flakes or silica flakes coated with titanium dioxide.

According to a fourth aspect of the present invention, there is provided a wireless communication device,
In the invention according to claim 3, the titanium dioxide is a rutile type.

According to a fifth aspect of the present invention, there is provided a wireless communication device,
The invention according to any one of claims 2 to 4, wherein the bright pigment is obtained by coating glass flakes or silica flakes with a thin film of a metal oxide having a thickness of 40 to 300 nm.

A wireless communication device according to the invention of claim 6 is
In the invention of claim 2, the bright pigment is obtained by coating glass flakes or silica flakes with a metal thin film having a thickness of 30 to 200 nm.

A wireless communication device according to the invention of claim 7 is
In the invention according to claim 1, the resin composition or the coating film contains at least one of glass flakes and silica flakes in an amount of 5 to 30% by weight.

The wireless communication device of the invention described in claim 8 is
In the invention according to any one of claims 2 to 5, the resin composition or the coating film contains 1 to 30% by weight of the bright pigment coated with a metal oxide.

According to a ninth aspect of the present invention, there is provided a wireless communication device,
In the invention according to claim 2 or 6, the resin composition or the coating film contains 1 to 20% by weight of the bright pigment coated with a metal.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below. However, the present invention is not limited to this embodiment.

The glass flakes or silica flakes (hereinafter referred to as "base material") are insulators and have no radio wave shielding property. Further, it is a scaly powder having no absorption band in the visible light region and having extremely high surface smoothness. Therefore, the light reflected on the surface of the base material is not colored or scattered, and the brightness before the reflection is maintained almost as it is. Further, since this base material has no cleavage property, it is difficult to be crushed when compounded and kneaded with the resin composition or the paint. Therefore, when the base material is blended and added to the resin composition or the paint as it is,
The resin composition or the coating film does not block radio waves and exhibits a brilliance equal to or higher than that when a conventional luster pigment is used. That is, a member molded of a resin composition containing this base material, or a member provided with a coating film containing this base material can enhance its design while satisfying the characteristics required for a wireless communication device. . The silica flakes refer to scaly powder made of only silicon oxide.

The shape of the substrate has an average particle size of 5 to 1,000 μm.
The average thickness is preferably 0.5 to 5 μm. The average particle diameter is the average of the longest diameters on a smooth surface. If the average particle size is too large, the base material is easily crushed when blending and kneading with the resin composition or the paint, and it becomes difficult to maintain the initial particle size. Also,
When the substrate is coated with a thin film of metal or metal oxide as described below, the fractured surface of the substrate that is not coated with metal or metal oxide appears when the substrate is crushed. There is also a problem that the glittering feeling of On the other hand, if it is too small, the base material faces different directions in the resin composition or the coating film, and the directions of reflected light also become different, so that the reflected light seems to be scattered and the glittering feeling is deteriorated. When the average thickness of the base material is less than 0.5 μm,
Since the strength is insufficient, the base material is deformed in the resin composition or the coating film, the smooth surface is curved, and the reflected light is easily scattered.
On the other hand, when the thickness is more than 5 μm, the flexibility of the base material is lowered, so that the base material is easily damaged when blending and kneading with the resin composition or the coating material.

By coating this substrate with a thin film of a metal or a metal oxide, it is possible to further increase the brightness of the light reflected on the surface and to impart a metallic color to the reflected light. Hereinafter, the base material coated with a metal or a metal oxide is referred to as a "bright pigment". The bright pigment is formed by forming a thin film of a metal or a metal oxide on the surface of a base material having a high surface smoothness by a sputtering method or a solution deposition method, so that the surface state of the base material is directly reflected on the surface. Becomes extremely smooth. Furthermore, when the bright pigment has a thin film of a metal oxide, the refractive index of the substrate is 1.5.
Since the refractive index of the metal oxide is generally higher than that before and after the difference, the difference in the refractive index from the atmosphere on the surface of the bright pigment becomes large, and the increase in the difference in the refractive index makes the reflection more likely to occur. If the bright pigment has a thin metal film, the reflected light will have a color peculiar to the metal.

The metal constituting the thin film is not particularly limited, but gold, silver, nickel, nickel alloy,
Examples are copper, tin, zinc or alloys thereof. However, as the metal thin film becomes thicker, the radio wave shielding property becomes more remarkable, so that the thickness must be suppressed to 200 nm or less. On the other hand, in order to reflect visible light, at least 30
nm is required.

The metal oxide is not particularly limited, and examples thereof include titanium dioxide, tin oxide, zinc oxide, indium-doped tin oxide (ITO), aluminum oxide, iron oxide, silicon oxide, zirconium oxide, and oxide. Examples include bismuth and cerium oxide. Of these, rutile type titanium dioxide is preferable. Rutile-type titanium dioxide has higher chemical stability and higher refractive index than anatase-type titanium dioxide, and is a typical one and has a refractive index of 2.70.

The metal oxide is generally an insulator and a part thereof is a semiconductor. Therefore, the bright pigment coated with the metal oxide does not cause radio interference. Further, since the metal oxide is almost colorless, its reflected light is not colored. In other words, this means that the reflected light is not absorbed, that is, the reflected light can maintain high brightness.

The thickness of the metal oxide thin film is 40 to 300.
nm is preferred. If it is less than 40 nm, the function of increasing the brightness of reflected light and the function of preventing the elution of alkali components are not sufficiently exhibited. On the other hand, if it exceeds 300 nm, the flexibility of the substrate may be impaired. Since the metal oxide thin film is usually transparent, light is reflected by the surface of the thin film and the surface of the base material. Therefore, the light reflected on the surface of the thin film and the light reflected on the surface of the base material interfere with each other,
May exhibit interference colors. The condition for exhibiting the interference color is derived from a well-known relational expression between the thickness and the refractive index of this thin film.
While satisfying the relational expression, a metal oxide thin film having a thickness within the above range may be formed.

When the base material is glass flakes, it is known that the contained alkaline component elutes from the surface thereof over time. The elution of the alkaline component deteriorates the resin or paint component that comes into contact with it, and also reduces the surface smoothness of the glass flake itself. In the case of a bright pigment, the thin film of metal or metal oxide covers the entire surface of the glass flakes, so that the elution of this alkaline component can be suppressed. In particular, the metal oxide thin film has high chemical durability and is effective in preventing elution of alkali components.

Illustrative examples of glitter pigments include the glitter pigment metashine series manufactured by Nippon Sheet Glass Co., Ltd.
Specifically, metashine nickel series (MC5480NS, MC5480NS, MC
5230NS, MC5150NS, MC5140NS, MC5090NS, MC5030NS, MC
5480NB, MC5230NB, MC5150NB, MC5140NB, MC5090NB, MC
5030NB, MC1040NB, MC1020NB), silver electroless plated metashine silver series (MC5480PS, MC5230PS,
MC5150PS, MC5140PS, MC5090PS, MC5030PS, MC2080PS,
MC2040PS, MC2025PS), metashine gold series electrolessly plated with gold, metashine in tania coat series coated with rutile titanium dioxide (MC5030RS, MC)
5090RS, MC5090RY, MC5090RR, MC5090RB, MC5090RG, MC
1080RS, MC1080RY, MC1080RR, MC1080RB, MC1080RG, MC
1040RS, MC1040RY, MC1040RR, MC1040RB, MC1040RG, MC
1020RS, MC1020RY, MC1020RR, MC1020RB, MC1020RG) etc. You may use these individually or in mixture of 2 or more types.

Further, these bright pigments may be surface-treated with silica or a coupling agent in order to improve water resistance and kneadability with a resin composition and a paint, and in order to improve light resistance, It may be a molded ultraviolet absorbing thin film.

When glass flakes or silica flakes are blended with the coating material, the content thereof is preferably 5 to 30% by weight when the solvent in the coating material is removed to form a coating film. In addition, it is preferable that the content is also equal when compounded in the resin composition. If it is less than 5% by weight, the luster feeling is insufficient, while if it exceeds 30% by weight, the relative amount of the resin component is insufficient and the integrity of the coating film and the resin composition is impaired.

When the bright pigment having a thin film of metal oxide is blended and added to the resin composition or the coating film, its content is preferably 1 to 30% by weight in the state where the solvent is removed. When this content is less than 1% by weight, the glittering property tends to be insufficient, while when it exceeds 30% by weight, the ratio of the resin component in the resin composition or the coating film is relatively decreased, and the strength thereof is reduced. May be damaged. A more preferable content ratio is 5 to 15% by weight.

When the bright pigment having a thin metal film is blended and added to the resin composition or the coating film, its content is preferably 1 to 20% by weight in the state where the solvent is removed. Further, 5 to 15% by weight is suitable. If the content is less than 1% by weight, the glittering property is insufficient, while if it exceeds 20% by weight, the glittering pigments come into contact with each other, and conductivity or magnetism may appear to impair radio wave transmission. There is.

The type of the resin component in the resin composition or the resin component in the paint is not particularly limited. For example, an acrylic resin as the thermosetting resin,
Polyester resin, epoxy resin, phenol resin, urea resin, fluororesin, polyester-urethane curing resin, epoxy-polyester curing resin, acrylic-polyester resin, acrylic-urethane curing resin, acrylic-melamine curing resin or polyester Examples of the thermoplastic resin such as melamine curable resin include polyethylene resin, polypropylene resin, petroleum resin, thermoplastic polyester resin, and thermoplastic fluororesin.
Since a thermoplastic resin can be injection-molded, a molded product having a complicated shape can be obtained. Further, as a curing agent, polyisocyanate, amine, polyamide, polybasic acid,
An acid anhydride, polysulfide, trifluoroboric acid, acid dihydrazide or imidazole can be used. Further, in addition to the above-mentioned base material and bright pigment, other coloring pigments having neither conductivity nor magnetism may be mixed and added to the resin composition or the coating film.

The coating film and resin composition containing the glass flakes, silica flakes and / or luster pigment exhibit a high luster due to reflected light without blocking radio waves, so that it can be used for housings and wireless communication devices. It can be used as each component of.

[0033]

The present invention will be described in more detail with reference to the following examples. However, it is not limited to the following examples.

(Example 1) Glass flakes coated with nickel by electroless plating (MC10 manufactured by Nippon Sheet Glass Co., Ltd.)
40NB Average particle diameter 40 μm Average thickness 1 μm Nickel film thickness 100 nm) A bright pigment composed of a urethane clear paint was kneaded so that the content in the coating film was 5% by weight, and a thickness of 0 was prepared in advance. The paint was applied to a polyester film having a thickness of 0.3 mm so as to have an average film thickness of 200 μm. After confirming that the test piece was completely dried, the test piece was cut into a 150 × 150 mm test piece, and TR-17301A and R3361A manufactured by Advantest were used together to measure the electromagnetic wave shielding function of the test piece. This measuring method is a method of evaluating the so-called shielding effect as a shielding effect against electric field waves and magnetic field waves in nearby electromagnetic waves, depending on the source of electromagnetic waves. The electromagnetic wave shield effect (SE) is E1 (V / m) when the shield material is placed, and SE = 20 × log ( It is defined by E0 / E1) (dB). However, it is assumed that the incident electromagnetic wave is a plane wave, the size of the shield material is infinitely large, and the electromagnetic wave is vertically incident on the shield material.

The result of measurement in the frequency range of 0 to 1,000 MHz is shown in FIG. From FIG. 1, it can be seen that this test piece does not shield electromagnetic waves at all. That is, it can be said that a coating film containing this bright pigment can be used as a coating film for a wireless communication device. Further, in a room of ordinary brightness, the sensation of glitter of this test piece was visually evaluated by five sensory testers. As a result, all the sensory testers evaluated that the luster was higher than that of the test piece of Comparative Example 1 below.

(Comparative Example 1) In Example 1, aluminum flakes commercially available as a luster pigment instead of the bright pigment (Alpaste 01 manufactured by Toyo Aluminum Co., Ltd.)
00X average particle diameter 45 μm average thickness 0.3 μm), a test piece was prepared in the same manner except that the electromagnetic wave shielding function was measured. The measurement result is shown in FIG.

From FIG. 2, it can be seen that this test piece exhibits a maximum shield effect of 80 dB. This is a level at which communication failure occurs in mobile phones and the like. In addition, the evaluation results of the glittering feeling by the five sensory testers are that although there is a glittering feeling,
When compared with the test piece of Example 1, the difference in brilliance was clear.

[0038]

INDUSTRIAL APPLICABILITY The present invention provides a wireless communication comprising a base material having no radio wave shielding property and / or a resin composition containing an appropriate amount of a bright pigment having no or low electromagnetic wave shielding property and / or a constituent member provided with a coating film. Since it is a device, it is possible to have a high designability derived from a glittering feeling without causing communication trouble.

[Brief description of drawings]

FIG. 1 is a diagram showing a measurement result of an electromagnetic wave shielding function in Example 1.

FIG. 2 is a diagram showing a measurement result of an electromagnetic wave shielding function in Comparative Example 1.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takenori Shinohara             7-28 Kitahama 4-28, Chuo-ku, Osaka City, Osaka Prefecture             Within Nippon Sheet Glass Co., Ltd. F-term (reference) 4E360 EE12 GA34 GA51 GB26 GC08                       GC11                 5K023 AA07 BB01 BB28 RR05

Claims (9)

[Claims] 1. A wireless communication device comprising a member molded of a resin composition containing glass flakes or silica flakes, or a member provided with a coating film containing glass flakes or silica flakes. 2. A radio comprising a member molded of a resin composition containing a bright pigment, which is obtained by coating glass flakes or silica flakes with a metal or a metal oxide, or a member provided with a coating film containing the bright pigment. Communication equipment. 3. The wireless communication device according to claim 2, wherein the bright pigment is glass flakes or silica flakes coated with titanium dioxide. 4. The wireless communication device according to claim 3, wherein the titanium dioxide is a rutile type. 5. The bright pigment is glass flakes or silica flakes coated with a thin film of a metal oxide having a thickness of 40 to 300 nm.
The wireless communication device according to item. 6. The wireless communication device according to claim 2, wherein the bright pigment is glass flakes or silica flakes covered with a thin metal film having a thickness of 30 to 200 nm. 7. The resin composition or coating comprises 5 to 3 of at least one of glass flakes and silica flakes.
The wireless communication device according to claim 1, wherein the wireless communication device contains 0% by weight. 8. The wireless communication device according to claim 2, wherein the resin composition or the coating film contains a bright pigment coated with a metal oxide in an amount of 1 to 30% by weight. . 9. The wireless communication device according to claim 2, wherein the resin composition or the coating film contains a bright pigment coated with a metal in an amount of 1 to 20% by weight.